Levich Institute Seminar Announcement,
01/30/2007

2:00 PM Steinman Hall, Room #312 (Chemical Engineering Conference Room) Professor Michael Booty Mathematical Sciences Department New Jersey Institute of Technology (Currently on Sabbatical at CCNY) "Steady and TipStreaming Solutions of a Slender SurfactantCoated Bubble in an Extensional Flow" 
Slender body theory is used to find the steady deformation and timedependent evolution of an axisymmetric inviscid bubble in a zeroReynoldsnumber extensional flow when insoluble surfactant is present on the bubble surface. The solutions show steady ellipsoidal bubbles that are completely covered by surfactant and, at increasing strain rate, solutions that are surfactantfree on a central cylindrical part with semiellipsoidal surfactantcovered end caps. Simple expressions are found for the steadystate response relation between the capillary number and the bubble slenderness ratio, which show the presence of a finite critical capillary number (and hence a finite critical imposed strain rate) above which the steady solutions cease to exist. Simplified equations are shown that describe timedependent behavior reminiscent of tipstreaming when the capillary number is above critical. Recent results are described indicating how effects such as interior bubble viscosity or solubility of surfactant in the exterior bulk flow can modify the solution structure. BRIEF ACADEMIC/EMPLOYMENT BACKGROUND: 